Bed nets are a common and effective way to prevent malaria transmission by mosquitoes. However, in some parts of the world, mosquitoes have developed "behavioral resistance," in which they have learned to avoid bed nets by biting people earlier in the day.

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Bed nets are a common and effective way to prevent malaria transmission by mosquitoes. However, in some parts of the world, mosquitoes have developed "behavioral resistance," in which they have learned to avoid bed nets by biting people earlier in the day.